903 resultados para black sage


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Grounded in group conflict theory and the defended neighborhoods thesis, this nationwide empirical study of cities and their residential segregation levels, examines the occurrence of hate crime using data on for all U.S. cities with populations over 95,000, and data compiled from the Uniform Crime Report for hate crime, in conjunction with 2000 census data. Hate crime is any illegal act motivated by pre-formed bias against, in this case, a person’s real or perceived race. This research asks: Do hate crime levels predict white/black segregation levels? How does hate crime predict different measures of white/black segregation? I use the dissimilarity index measure of segregation operationalized as a continuous, binary and ordinal variable, to explore whether hate crime predicts segregation of blacks from whites. In cities with higher rates of hate crime there was higher dissimilarity between whites and blacks, controlling for other factors. The segregation level was more likely to be “high” in a city where hate crime occurred. Blacks are continually multiply disadvantaged and distinctly affected by hate crime and residential segregation. Prior studies of residential segregation have focused almost exclusively on individual choice, residents’ lack of finances, or discriminatory actions that prevent racial minorities from moving, to explore the correlates of segregation. Notably absent from these studies are measures reflecting the level of hate crime occurring in cities. This study demonstrates the importance of considering hate crime and neighborhood conflict when contemplating the causes of residential segregation.

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In order to display a homogeneous image using multiple projectors, differences in the projected intensities must be compensated. In this paper, we present novel approaches to combine and extend existing techniques for edge blending and luminance harmonization to achieve a detailed luminance control. Furthermore, we apply techniques for improving the contrast ratio of multi-segmented displays also to the black offset correction. We also present a simple scheme to involve the displayed context in the correction process to dynamically improve the contrast in brighter images. In addition, we present a metric to evaluate the different methods and their influence on the visual quality.

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The study of natural magnetic sands is instrumental to investigate the geological aspects of their formation and of the origin of their territory. In particular, Mössbauer spectroscopy provides unique information on their iron content and on the oxidation state of iron in their mineral composition. The Italian coast on the Mediterranean Sea near Rome is known for the presence of highly magnetic black sands of volcanic origin. A study of the room temperature Mössbauer spec- trum, powder X-ray diffraction, energy dispersive X-ray spectroscopy, and magnetic measurements of a sample of black magnetic sand collected on the seashore of the town of Ladispoli is performed. This study reveals magnetite as main constituent with iron in both tetrahedral and octahedral sites. Minor constituents are the iron minerals hematite and ilmenite, the iron containing minerals diopsite, gossular, and allanite, as well as ubiquitous sanidine, quartz, and calcite.

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We propose a simple implementation of Black’s (1988) elegant rule for discounting uncertain future cash flows. Black’s rule avoids the thorny problem of estimating an appropriate risk-adjusted discount rate. Instead, the rule calls for discounting conditional mean cash flows at appropriate riskless interest rates. Our contribution in this article is to describe and illustrate a method of estimating the conditional mean cash flows called for in Black’s rule. The method is quite flexible with respect to the types of information available concerning the distributions of future cash flows. We argue that this approach to computing present values offers a theoretically sound and generally feasible addition to the toolbox of financial managers.

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The objective of the study was to determine if there are sex-based differences in the prevalence and clinical outcomes of subclinical peripheral artery disease (PAD). We evaluated the sex-specific associations of ankle-brachial index (ABI) with clinical cardiovascular disease outcomes in 2797 participants without prevalent clinical PAD and with a baseline ABI measurement in the Health, Aging, and Body Composition study. The mean age was 74 years, 40% were black, and 52% were women. Median follow-up was 9.37 years. Women had a similar prevalence of ABI < 0.9 (12% women versus 11% men; P = 0.44), but a higher prevalence of ABI 0.9-1.0 (15% versus 10%, respectively; P < 0.001). In a fully adjusted model, ABI < 0.9 was significantly associated with higher coronary heart disease (CHD) mortality, incident clinical PAD and incident myocardial infarction in both women and men. ABI < 0.9 was significantly associated with incident stroke only in women. ABI 0.9-1.0 was significantly associated with CHD death in both women (hazard ratio 4.84, 1.53-15.31) and men (3.49, 1.39-8.72). However, ABI 0.9-1.0 was significantly associated with incident clinical PAD (3.33, 1.44-7.70) and incident stroke (2.45, 1.38-4.35) only in women. Subclinical PAD was strongly associated with adverse CV events in both women and men, but women had a higher prevalence of subclinical PAD.

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We present the first-order corrected dynamics of fluid branes carrying higher-form charge by obtaining the general form of their equations of motion to pole-dipole order in the absence of external forces. Assuming linear response theory, we characterize the corresponding effective theory of stationary bent charged (an)isotropic fluid branes in terms of two sets of response coefficients, the Young modulus and the piezoelectric moduli. We subsequently find large classes of examples in gravity of this effective theory, by constructing stationary strained charged black brane solutions to first order in a derivative expansion. Using solution generating techniques and bent neutral black branes as a seed solution, we obtain a class of charged black brane geometries carrying smeared Maxwell charge in Einstein-Maxwell-dilaton gravity. In the specific case of ten-dimensional space-time we furthermore use T-duality to generate bent black branes with higher-form charge, including smeared D-branes of type II string theory. By subsequently measuring the bending moment and the electric dipole moment which these geometries acquire due to the strain, we uncover that their form is captured by classical electroelasticity theory. In particular, we find that the Young modulus and the piezoelectric moduli of our strained charged black brane solutions are parameterized by a total of 4 response coefficients, both for the isotropic as well as anisotropic cases.

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Hydrodynamics can be consistently formulated on surfaces of arbitrary co-dimension in a background space-time, providing the effective theory describing long-wavelength perturbations of black branes. When the co-dimension is non-zero, the system acquires fluid-elastic properties and constitutes what is called a fluid brane. Applying an effective action approach, the most general form of the free energy quadratic in the extrinsic curvature and extrinsic twist potential of stationary fluid brane configurations is constructed to second order in a derivative expansion. This construction generalizes the Helfrich-Canham bending energy for fluid membranes studied in theoretical biology to the case in which the fluid is rotating. It is found that stationary fluid brane configurations are characterized by a set of 3 elastic response coefficients, 3 hydrodynamic response coefficients and 1 spin response coefficient for co-dimension greater than one. Moreover, the elastic degrees of freedom present in the system are coupled to the hydrodynamic degrees of freedom. For co-dimension-1 surfaces we find a 8 independent parameter family of stationary fluid branes. It is further shown that elastic and spin corrections to (non)-extremal brane effective actions can be accounted for by a multipole expansion of the stress-energy tensor, therefore establishing a relation between the different formalisms of Carter, Capovilla-Guven and Vasilic-Vojinovic and between gravity and the effective description of stationary fluid branes. Finally, it is shown that the Young modulus found in the literature for black branes falls into the class predicted by this approach - a relation which is then used to make a proposal for the second order effective action of stationary blackfolds and to find the corrected horizon angular velocity of thin black rings.

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Aim: We aimed to assess caries experience and microbiota in systemically healthy children with black stain (BS) and non-discoloured plaque. Methods: Forty-six children with BS and 47 counterparts with non-discoloured plaque aged 7.9 ± 1.3 years were clinically examined. Dental caries was scored using WHO criteria. Samples of BS and non-discoloured dental plaque were collected from tooth surfaces. The DNA of the samples was extracted and real-time PCR was performed to determine the total number of bacteria and the species Streptococcus mutans, S. sobrinus, Lactobacillus sp., Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum. Results: Children with BS had lower DMFT (p = 0.013), lower DT values (p = 0.005) and a tendency to lower caries prevalence (p = 0.061) than children with non-discoloured plaque. Plaque samples of the BS group contained higher numbers of A. naeslundii (p = 0.005) and lower numbers of F. nucleatum (p = 0.001) and Lactobacillus sp. (p = 0.001) compared to the non-discoloured plaque samples of the control group. Comparing the children with BS and non-discoloured plaque, higher counts for A. naeslundii (p = 0.013) were observed in caries-free children with BS while in caries-affected children with BS, lower counts of F. nucleatum (p = 0.007) were found. Counts of Lactobacillus sp. were higher in non-discoloured plaque samples than in BS of caries-free and caries-affected children. Conclusion: Results suggest that the different microbial composition of BS might be associated with the lower caries experience in affected subjects. The role of black-pigmented bacteria associated with periodontitis needs further studies. © 2013 S. Karger AG, Basel.

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This multiproxy study on SE Black Sea sediments provides the first detailed reconstruction of vegetation and environmental history of Northern Anatolia between 134 and 119 ka. Here, the glacial–interglacial transition is characterized by several short-lived alternating cold and warm events preceding a meltwater pulse (~ 130.4–131.7 ka). The latter is reconstructed as a cold arid period correlated to Heinrich event 11. The initial warming is evidenced at ~ 130.4 ka by increased primary productivity in the Black Sea, disappearance of ice-rafted detritus, and spreading of oaks in Anatolia. A Younger Dryas-type event is not identifiable. The Eemian vegetation succession corresponds to the main climatic phases in Europe: i) the Quercus–Juniperus phase (128.7–126.4 ka) indicates a dry continental climate; ii) the Ostrya–Corylus–Quercus–Carpinus phase (126.4–122.9 ka) suggests warm summers, mild winters, and high year-round precipitation; iii) the Fagus–Carpinus phase (122.9–119.5 ka) indicates cooling and high precipitation; and iv) increasing Pinus at ~ 121 ka marks the onset of cooler/drier conditions. Generally, pollen reconstructions suggest altitudinal/latitudinal migrations of vegetation belts in Northern Anatolia during the Eemian caused by increased transport of moisture. The evidence for the wide distribution of Fagus around the Black Sea contrasts with the European records and is likely related to climatic and genetic factors.

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In order to compare the sea-surface conditions in the Black Sea during the Holocene and Eemian, sapropelic parts of marine core 22-GC3 (42°13.53′N/36°29.55′E, 838 m water depth) were studied for organic-walled dinoflagellate cyst content. The record shows a change from freshwater/brackish assemblages (Pyxidinopsis psilata, Spiniferites cruciformis, and Caspidinium rugosum) to more marine assemblages (Lingulodinium machaerophorum and Spiniferites ramosus complex) during each interglacial, due to the inflow of saline Mediterranean water. The lacustrine–marine transitions in 22-GC3 occurred at ~ 8.3 cal kyr BP during the early Holocene and ~ 128 kyr BP during the early Eemian, slightly later compared to the onset of interglacial conditions on the adjacent land. Dinoflagellate cyst assemblages reveal higher sea-surface salinity (~ 28–30) (e.g. Spiniferites pachydermus, Bitectatodinium tepikiense, and Spiniferites mirabilis) around ~ 126.5–121 kyr BP in comparison to the Holocene (~ 15–20) as well as relatively high sea-surface temperature (e.g. Tuberculodinium vancampoae, S. pachydermus, and S. mirabilis) especially at ~ 127.6–125.3 kyr BP. Establishment of high sea-surface salinity during the Eemian correlates very well with reconstructed relatively high global sea-level and is explained as a combined effect of increased Mediterranean supply and high temperatures at the beginning of the last interglacial. The observed changes in the dinocyst record highlight the importance of nutrients for the composition of the Eemian and Holocene dinocyst assemblages.